1. Field of the Invention
The present invention relates to a process for stabilizing a polyol fatty acid polyester. The polyol fatty acid polyester stabilized by the process according to the invention may be used as an edible fat substitute having no calories.
2. Related Art
Polyol fatty acid esters have, in general, been utilized as emulsifiers, as exemplified by sucrose fatty acid esters, which have a structure, wherein the hydroxy radical(s) in a polyol, for instance saccharide or sugar alcohol and the fatty acid(s) are esterified, at an esterification degree not higher than 50%.
Recently, however, polyol fatty acid polyesters having esterification degree higher than 40% and more preferably higher than 50% have been watched with great interest, as an edible fat substitute having no calories or as a substance to be composed to an edible fat to decrease total calories of the resulting composition, since such polyol fatty acid polyesters are neither digested nor assimilated in the digestive canal and their physico-chemical properties thereof are analogous to usual edible fats. For instance, Jap. Pat. No. Sho 61-15046 (B) discloses a composition for foods, which comprises polyol fatty acid polyesters and vitamins.
The polyol fatty acid polyesters, for instance the sucrose fatty acid polyester has been prepared by, for instance, a method wherein sucrose is reacted with a fatty acid ester(s), in the presence of a solvent and an alkali catalyst [Jap. Pat. Nos. Sho 62-129242(A) and Sho 62-215598(A)].
Hitherto, it has been so considered that the polyol fatty acid polyester shows a specific or inherent stability to be estimated from its constitutional fatty acids but, in actuality, a product with constant stability has not been obtained. Although a cause generating the fluctuation in stability has not yet been elucidated, the catalyst employed for its synthesis and which possibly remains in the product, may be one of the causes.
When the polyol fatty acid polyester shall be used as the edible fat substitute and more particularly, in the field of foods, the low in stability thereof becomes a remarkable disadvantage in the view point of preservation of health.